From the 1950s–1990s, mortar was typically used to set roof tiles on Naples-area homes, but the wind damage caused by the devastating hurricanes of 1992 and 2004 showed the vulnerability of this installation method. Since then, new installation techniques have been introduced that help reduce uplift and improve wind mitigation, in particular foam adhesives and screws.
Foam
The main advantages of using foam instead of mortar is that foam is lightweight and provides strong adhesion without any need for putting fastener holes in the roof. An additional, little-known benefit is that foam acts as a pad to cushion foot traffic and expansion/contraction, which lessens the risk of cracked tiles. While foam has shown that it’s a good concept, in practice, this attachment method is not the best answer for several reasons:
- When foam adhesive is used, the weight of each tile gets transferred to the underlayment, and this can cause the underlayment to slide, leaving open gaps in the roofing.
- While wind resistance is improved using foam, Florida’s building code still requires that the first row of tiles is mechanically fastened as well, because tile roofs tend to fail around the perimeter where wind uplift is more severe.
- Fasteners are also necessary on steeply-pitched roofs, because underlayment and tile manufacturers recognize that underlayment can only withstand so much gravitational pull without sliding.
Screws
The post-Hurricane Andrew era also saw the introduction of nails and screws to boost wind resistance in tile roof installations. Compared to nails, screws have the advantage of not backing out. Screws also self-seal as they’re driven down through the underlayment, and they transfer the weight of each tile down to the roof’s structure so the underlayment isn’t relied on or made vulnerable to slipping.
Hybrid Installation Offers The Best of Both Worlds
A truly superb tile roof is installed using a combination of foam adhesive and screws – it has the solid wind resistance and weight transfer provided by screws, which allows greater flexibility in underlayment options. Using foam adhesive at the tiles’ leading edge effectively glues down the area most prone to uplifting. This gives the roof incredible wind uplift resistance plus built-in cushioning against tile breakage. During testing, this hybrid installation method shows the highest wind uplift resistance ever achieved, and it’s capable of withstanding even the most severe hurricane-force winds.
For expert hybrid tile roofing in Naples, contact us at Kelly Roofing today.
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